The field of the invention relates generally to monitoring generators and, more particularly, to methods and systems to monitor a generator for sparking and discharge events.
Carbon brushes in a generator collector assembly conduct current from a stationary position to a rotating collector. Some non-destructive sparking at the brushes is common and generally does not produce excessive wear on the brushes or erosion of the collector ring surfaces. Collector flashover, however, is a common cause of a generator outage. Flashover describes the opening of the highly inductive generator field circuit and can occur at positive or negative polarity. Flashover often occurs after carbon brushes have been sparking for a long time.
A common method of preventing collector flashover in a generator collector assembly is to routinely inspect, maintain, and overhaul the generator. There are several measurements and checklists that facilitate such maintenance. Commercially available systems do not, however, provide an in-situ, continuous monitoring system for preventive and planned maintenance.